An older sedating antihistamine for allergy and itch
Tripelennamine
An older sedating antihistamine used to ease allergy symptoms and itching, which commonly causes drowsiness.
What is Tripelennamine?
Tripelennamine is an older, first-generation antihistamine used to relieve allergy symptoms such as a runny nose and sneezing, and to ease itching. It works by blocking histamine, the chemical released during allergic reactions. Because it is a sedating antihistamine, it commonly causes drowsiness and can have antimuscarinic effects such as a dry mouth, blurred vision and constipation. It is an older medicine, used less often now that non-drowsy antihistamines are available, and in some combinations it has been linked with misuse. It should be used with care if you need to drive or operate machinery.
Education and reference only. This is a plain-language guide to Tripelennamine — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Tripelennamine is a first-generation, or sedating, antihistamine. Antihistamines are medicines that block the effects of histamine, a natural chemical the body releases during allergic reactions, which causes symptoms such as itching, sneezing and a runny nose. Tripelennamine is one of the older antihistamines, developed before the modern non-drowsy ones, and it is used to ease allergy symptoms and itch. Because it is the sedating kind, it tends to cause drowsiness. It is used less commonly today than newer antihistamines, and it should always be used as directed.
How it works
During an allergic reaction, the body releases histamine, which attaches to receptors and triggers itching, sneezing, a runny nose and other symptoms. Tripelennamine works by blocking these histamine receptors, so histamine can no longer cause those symptoms. Because it is an older antihistamine that crosses into the brain easily, it also causes drowsiness and can produce antimuscarinic effects such as a dry mouth and blurred vision. This sedating effect is the main difference from the newer, non-drowsy antihistamines, which are designed to act mostly outside the brain.
Company & origin
Originated / developed by: Generic (long-established).
An older antihistamine used to relieve allergy symptoms and itch, belonging to the sedating first-generation group.
What it treats
Conditions Tripelennamine is used for
Practical use
How to take Tripelennamine
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it as directed by your prescriber or pharmacist, and do not take more than advised.
- Be aware it can make you drowsy, so take care with driving, operating machinery or tasks needing concentration.
- Avoid alcohol while taking it, as alcohol increases the drowsiness.
- Tell your prescriber about other medicines, especially those that also cause drowsiness or a dry mouth.
- Use it only as advised, and speak to a pharmacist about non-drowsy alternatives if drowsiness is a problem.
Weighing it up
Advantages & disadvantages of Tripelennamine
Advantages
- Eases allergy symptoms such as sneezing, a runny nose and itching.
- Helps relieve itch, and its sedating effect can be useful when itching disturbs sleep.
- A long-established medicine with decades of use behind it.
Disadvantages
- Commonly causes drowsiness, which can affect driving and concentration.
- Can cause antimuscarinic effects such as a dry mouth, blurred vision and constipation.
- An older medicine that has, in some combinations, been linked with misuse, so non-drowsy options are often preferred.
Practical use
Good to know
The most noticeable thing about tripelennamine is that it commonly causes drowsiness, so it can affect your ability to drive, operate machinery or concentrate, and these effects are made worse by alcohol. It can also cause antimuscarinic effects such as a dry mouth, blurred vision, constipation and difficulty passing urine, which can be more troublesome in older people. Because it is an older, sedating antihistamine, many people are now offered a non-drowsy alternative for everyday allergy symptoms. A point worth knowing is that, in certain combinations, this type of medicine has been linked with misuse, so it should only be used as prescribed or advised. Tell your prescriber or pharmacist about other medicines, as combining several that cause drowsiness or antimuscarinic effects can add up.
Who should not take it / use with caution
- People who have had a serious allergic reaction to tripelennamine should not take it.
- It is used with caution in older people, who are more sensitive to drowsiness and antimuscarinic effects.
- It is used with care in people with glaucoma, an enlarged prostate or difficulty passing urine.
- It is used with care in pregnancy and breastfeeding, on medical advice.
Monitoring
- Reviewing whether allergy symptoms or itch are well controlled.
- Checking that drowsiness or antimuscarinic effects are not causing problems, especially in older people.
- Considering a non-drowsy antihistamine if side effects are troublesome.
Side effects
- Drowsiness or feeling sleepy, which is common.
- A dry mouth, blurred vision, constipation or difficulty passing urine.
- Dizziness, headache or stomach upset in some people.
Key interactions
- Alcohol and other medicines that cause drowsiness, such as sedatives, can add to its sedating effect.
- Other medicines with antimuscarinic effects can combine with it to cause a dry mouth, constipation or urinary problems.
- Tell your prescriber or pharmacist about all your medicines before taking it.
Available as: Tablets taken by mouth (and, historically, other preparations).
Answers
Tripelennamine: frequently asked questions
What is tripelennamine used for?
It is an older sedating antihistamine used to relieve allergy symptoms such as sneezing and a runny nose, and to ease itching.
Why does it make me sleepy?
It is a first-generation antihistamine that crosses into the brain, so it commonly causes drowsiness, unlike the newer non-drowsy antihistamines.
Can I drink alcohol with it?
It is best to avoid alcohol, as alcohol increases the drowsiness this medicine can cause and makes it harder to concentrate.
Why might a non-drowsy antihistamine be better?
For everyday allergy symptoms, many people are offered a non-drowsy antihistamine instead, as tripelennamine commonly causes drowsiness and a dry mouth.
Is it safe for older people?
It is used with caution in older people, who are more sensitive to drowsiness and antimuscarinic effects such as confusion, a dry mouth and constipation.
The wider class
About Sedating (first-generation) antihistamine
Tripelennamine belongs to the sedating (first-generation) antihistamine class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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